COMPLIANCE INFO_FILE 1 2003-2006

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' 2) Sample 121/3S-0 was collected outside the "work area" identified in Figure 2 and appears to have an elevated copper concentration relative to the deeper soil ' samples collected below the depth of impacted material. To better define if soils in this area are impacted and determine the lateral extent of contamination please triangulate around this sample location and collect three surface samples ' for analysis for copper. An additional sample should be collected at depth at the location of 121/3S-0 to determine if the copper concentration observed in the original sample decreases with depth. If these samples indicate that elevated ' copper concentrations are present in the soils in this area, additional lateral and vertical characterization and or soil removal may be-necessary in this area. 3) Has the California Department of Fish and Game determination that a Notification of Lake or Streambed Alteration permit is not necessary been confirmed? 4) Based on the size of the proposed area for soil removal, at least ten confirmation soil samples should be collected. Three of the ten confirmation samples should be located in areas where elevated Copper concentrations were detected from previous sampling. The other seven confirmation samples should be spread out spatially in the remaining soil removal area. All confirmation samples should be analyzed for total copper. Based on a review of the CAM 17 analysis conducted on Sample 1 collected by the San Joaquin County Environmental Health ' Division, the three confirmation samples collected beneath previously identified elevated Copper concentrations should be analyzed for total lead, total chromium and hexavalent chromium. Additionally, these metals should be ' analyzed in any background samples collected for comparison purposes. If metals concentrations in the confirmation samples are above those observed in the background samples, soluble metals testing will be necessary for the protection of surface water and groundwater evaluation. For confirmation samples that exceed background metals concentrations, appropriate solubility testing (either De-Ionized Waste Extraction Test (DI WET) or Standard Waste Extraction Test) should be conducted on some of these samples. When the confirmation sample total results are received, please consult with DTSC or the RWQCB to determine which samples should be analyzed for soluble metals and ' the appropriate analysis. It is recommended that after the solubility analysis is completed two options would be available: 1) If the results are low or non-detect (ND) there would be no need for further assessment and the results can be ' evaluated as part of the assessment; or, 2) If elevated soluble metals are detected and are suspected to also be present in the native material, then conduct solubility analysis on background samples for comparison purposes.